Root equals sum of children

Tree Binary Tree

84.9% acceptance

Feb 25, 2026

1564

1646

You are given the root of a binary tree that consists of exactly 3 nodes: the root, its left child, and its right child. Return true if the value of the root is equal to the sum of the values of its two children, or false otherwise.

Solution

Rust

Time O(1)

Space O(1)

LeetCode

solution.rs

use std::rc::Rc;
use std::cell::RefCell;
impl Solution {
  pub fn check_tree(root: Option<Rc<RefCell<TreeNode>>>) -> bool {
    let root = root.unwrap();
    let root = root.borrow();
    let left = root.left.as_ref().unwrap().borrow().val;
    let right = root.right.as_ref().unwrap().borrow().val;
    root.val == left + right
  }
}